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Maybe some others can explain it better than I can: Some Pipers and other planes had a gear that used something like the shock absorbers used on cars instead of the bungee cords. It was supposed to be a better system. I don't know if it is only shocks or contains springs with the shocks. EDMO

Edited 30 Jun 2016 by EDMO

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Maybe some others can explain it better than I can: Some Pipers and other planes had a gear that used something like the shock absorbers used on cars instead of the bungee cords. It was supposed to be a better system. I don't know if it is only shocks or contains springs with the shocks. EDMO

The hydrosorbs were used in conjunction with the bungees on the pipers. Its just basically an inline shock.

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I finally got to do a little playing with the gear. I made a mock-up and ran some tests, and here is what I found, or think I found anyhow. I documented what I did, and since the file is long, instead of posting it here and taking up space, I have attached it as a .doc file. If you are interested, you can read it, if not, ignore it. I figure if you guys find anything wrong, you'll soon let me know.

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I finally got to do a little playing with the gear. I made a mock-up and ran some tests, and here is what I found, or think I found anyhow. I documented what I did, and since the file is long, instead of posting it here and taking up space, I have attached it as a .doc file. If you are interested, you can read it, if not, ignore it. I figure if you guys find anything wrong, you'll soon let me know.

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I am going to try to build a set of gear to the dimensions and angles used on the Piper Cub. Has anybody built gear where the front leg comes straight down from the fuselage instead of leaning forward 3 7/8 inch. This would put the mains a bit farther back. It would make the gear leg and the cabane easier to build.\

It would make the tailwheel come up faster but what other effects might it have?

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Update on the gear. One possible fix for existing gear. I had two yokes made similar to the yoke on a universal joint. They were made out of 1 1/4 cold rolled square stock. I threaded them 3/4-16 inside, and turned that end round to give 3/8 inch wall thickness. The fork end I milled out 7/8 inch wide to provide +1/8 wall thickness, and drilled that 1/4 inch.

I then made new longer axles, but threaded the inboard end to give a tight fit on the thread. The fork was threaded on, then drilled and pinned. I had to make new lower spring strut rods since they are shorter than original. The only issue I had was that the axle end of the spring rod has to be canted a bit to fit to the existing cabane. That and the 3/4 inch tubing AirSpruce provided won't accept a 3/4 inch wheel bearing without polishing it first.

The top (spring) end of the inner rod should be doubled internally to avoid the hole tearing out. I saw that happen on a Super Cub clone.

I put the gear back on the plane, but have not tried it yet.

The other possible fix is to weld tabs to the existing axle tubes. I will try that next.

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Arent those the red springs that everyone decided that they would not allow enough travel? Leni replaced those with some SnoGo black springs that didn't bottom out so quick, and he made longer slots to allow more travel. EDMO

Update on the gear. One possible fix for existing gear. I had two yokes made similar to the yoke on a universal joint. They were made out of 1 1/4 cold rolled square stock. I threaded them 3/4-16 inside, and turned that end round to give 3/8 inch wall thickness. The fork end I milled out 7/8 inch wide to provide +1/8 wall thickness, and drilled that 1/4 inch.

I then made new longer axles, but threaded the inboard end to give a tight fit on the thread. The fork was threaded on, then drilled and pinned. I had to make new lower spring strut rods since they are shorter than original. The only issue I had was that the axle end of the spring rod has to be canted a bit to fit to the existing cabane. That and the 3/4 inch tubing AirSpruce provided won't accept a 3/4 inch wheel bearing without polishing it first.

The top (spring) end of the inner rod should be doubled internally to avoid the hole tearing out. I saw that happen on a Super Cub clone.

I put the gear back on the plane, but have not tried it yet.

The other possible fix is to weld tabs to the existing axle tubes. I will try that next.

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Actually they are die springs from McMaster Carr. 9584K98. They are six inches long, and will compress to 3 inches. McMaster also lists an eight inch spring. I have the numbers for the Ski-Doo springs. 503190854. They are readily available for about $50 each. I also kept the dimensions for the spring struts, and can make a replacement set without taking the gear back off the plane. I only need to make the spring carriers. Two bolts on each side changes them.

Incidentally, the Super Cub only has 3 1/2 inches of travel. Measured it myself.